In an air-conditioning apparatus such as a multi air-conditioner for buildings, a refrigerant is made to circulate between, for example, an outdoor unit, which is a heat source apparatus, disposed outside a building and an indoor unit disposed inside of the building. Through radiation or absorption of heat by the refrigerant, the heated or cooled air is carried to the space subjected to air-conditioning to perform cooling or heating. As for the refrigerant, HFC (hydrofluorocarbon) refrigerant is often used, for example. Alternatively, a natural refrigerant such as carbon dioxide (CO2) is proposed, as well.
In the air-conditioning apparatus called a chiller, cooling energy or heating energy is generated in the heat source apparatus disposed outside the building. By performing heat exchange with the refrigerant in a heat exchanger of a refrigeration cycle arranged in the outdoor unit, a heat medium such as water and anti-freezing liquid is heated or cooled and by carrying it to a fan coil unit, panel heater, or the like which is the indoor unit, cooling or heating has been performed. There also is an apparatus called a waste heat recovery type chiller in which four water pipelines are connected to a heat source apparatus to supply cooled or heated water and the like simultaneously. (Refer to Patent Literature 1, for example)    Patent Literature 1 Japanese Patent No. 2003-343936A